Git (and Mercurial and friends) have event hooks that can be used for a variety of automation tasks. For instance, I have a repository that consists of Sphinx documentation for a project. When my webserver's copy of the repo receives new changesets, it updates to tip, builds the HTML and PDF targets, and if successful deploys them into the appropriate web-accessible locations.
Here the git client includes logic to speak (translate to) ftp - which is great for this purpose.
What if you could say: `git push fleet master`
where fleet is a remote that translates git-speak into a deployment.
I realize - this is simply an imitation of Heroku. But, it may be interesting to flex git in this way: a code change protocol.
This and the recently discussed codeq could yield some very interesting possibilities.